If there is
one species of butterfly that gets the lepidotera-philes scales to stand up on
end, it’s the juniper hairstreak, Callophrys
g. gryneus. When I run into folks on
the Edge that are seeking out butterfly species, the juniper hairstreak is
always on the top of the list. And
usually, it is a butterfly that is seen uncommonly. In fact, I usually see this small butterfly only a handful of times each year. But the last 2 years, I have been observing a
plant called rattlesnake master, Eryngium
yuccifolium, growing along the sidewalk to the Eulett Center, and have been
amazed at the species diversity that feeds/visits this plant, one of which is
the juniper hairstreak. I would say this plant is mis-named as I have never seen a rattlesnake around the plant, but
it sure attracts hairstreaks. Now
granted, the Eulett Center is surrounded by numerous Eastern red cedar trees, Juniperus virginiana, the host plant of
the juniper hairstreak’s caterpillar, but the numbers of juniper hairstreak's
this year has been phenomenal.
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| Juniper hairstreak on rattlesnake master, avoiding the white-banded crab spider, Misumenoides formosipes on the left. |
Throughout July, every time I
walk the 100 foot long sidewalk of the Eulett Center, I'd check out the 100 or so individual
rattlesnake master plant heads. And this
mid-July, it was not hard to find dozens of juniper hairstreaks feeding. On July 20, 2016 I counted 55 juniper
hairstreaks while walking up the path.
10 of them were in one clump of flower heads.
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| Numerous juniper hairstreaks on rattlesnake master |
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| Notice the green scales on the wings of our only "green" butterfly. |
Rattlesnake
master is a prairie plant native to this part of Ohio, and grows commonly in
the preserve's prairies. But this is not a common plant outside of prairie
openings in Ohio. If you want to attract
juniper hairstreaks, and you have Eastern red cedars near-by, try planting rattlesnake master on your property. If there are any juniper hairstreaks around,
they will find it.
This plant is incredibly fun to watch blooming in July to see how many flies, wasps, beetles, spiders, moths, bees etc. land on its many flowers. Below are some interesting species seen visiting rattlesnake master.
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| A feather-legged fly, Trichopoda sp. |
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| Great black wasp, Sphex pennsylvanicus |
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| Black and yellow lichen moth, Lycomorpha pholus |
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| Juniper hairstreak near striped lynx spider, Oxyopes salticus |
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| Spotted thyris moth, Thyris maculata |
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| Myzinum wasp, Myzinum sp. |
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| A potter wasp, Monobia quadridens |
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| A paper wasp, Polistes exclamans |
Posted by: Mark Zloba
